scope:

INTRODUCTION

This module describes the parameters to be considered in the design or selection of a geographical relay interlocking system.

NR/L2/SIG/11201, Module B7, Section 3 laid down the requirements for interlocking controls and specified their tabulation in control tables. The application of the principles and requirements to route setting systems are summarised in NR/L2/SIG/11201, Module B7, Section 7. This module demonstrates how those controls may be provided by the use of geographical relay systems. Figures:1 to 6 identify how the standard controls are applied to some common geographical interlockings and enable a comparison with the other interlocking systems.